<template>
  <section class="todoapp">
    <!-- 除了驼峰, 还可以使用-转换链接 -->
    <TodoHeader @addTask="addTaskFn" :list ='list'></TodoHeader>
    <TodoMain :list='showList' @del='delFn'></TodoMain>
    <TodoFooter @changeType="typeFn" :type='getSel' :len ='showList.length' @clearTask="clearFn"></TodoFooter>
  </section>
</template>

<script>
// 1.0 样式引入
import "./styles/base.css"
import "./styles/index.css"
    
import TodoHeader from "./components/TodoHeader";
import TodoMain from "./components/TodoMain";
import TodoFooter from "./components/TodoFooter";


export default {
  components: {
    TodoHeader,
    TodoMain,
    TodoFooter,
  },
  data() {
    return {
      list: JSON.parse(localStorage.getItem('todolist')) || [],
      getSel : 'all'
    };
  },
  computed: {
    showList() {
      if( this.getSel === 'yes') {
return this.list.filter(item => item.isDone)
      } else if (this.getSel === 'no') {
        return this.list.filter(item => !item.isDone)
      } else {
       return this.list
      }
    }
  }, 
  methods :{
    //添加
    addTaskFn(task) {
// console.log('addTaskFn',task);
this.list.push({
  id:this.list.length ? this.list.at(-1).id + 1 : 100,
  name:task,
  isDone:false
})
    },
    //删除
    delFn(id) {
      // console.log(id);
      this.list = this.list.filter(item => item.id !== id)
    },
    typeFn(type) {
this.getSel = type
    },
    //清除
    clearFn() {
      // console.log(111);
      this.list = this.list.filter(item => !item.isDone)
    }
  },
  watch:{
    list:{
      deep : true,
      handler() {
        localStorage.setItem('todolist',JSON.stringify(this.list))
      }
    }
  }
};
</script>